package com.kongyz.protocol;



import io.protostuff.LinkedBuffer;
import io.protostuff.ProtostuffIOUtil;
import io.protostuff.Schema;
import io.protostuff.runtime.RuntimeSchema;
import org.objenesis.Objenesis;
import org.objenesis.ObjenesisStd;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

public class SerializationUtil {
    private static Map<Class<?>,Schema<?>> cachedSchema=new ConcurrentHashMap<Class<?>, Schema<?>>();

    private static Objenesis objenesis=new ObjenesisStd(true);

    public SerializationUtil() {
    }

    /**
     * 获得某个class的Schema
     * @param cls
     * @param <T>
     * @return
     */
    @SuppressWarnings("unchecked")
    private static <T> Schema<T> getSchema(Class<T> cls){
        Schema<T> schema= (Schema<T>) cachedSchema.get(cls);
        if(schema==null){
            schema= RuntimeSchema.createFrom(cls);
            if(schema!=null){
                cachedSchema.put(cls,schema);
            }
        }
        return schema;
    }

    /**
     * 序列化 （对象 -> 字节数组）
     * @param obj
     * @param <T>
     * @return
     */
    @SuppressWarnings("unchecked")
    public static <T> byte[] serializa(T obj){
        Class<T> cls= (Class<T>) obj.getClass();
        LinkedBuffer buffer=LinkedBuffer.allocate(LinkedBuffer.DEFAULT_BUFFER_SIZE);
        try {
            Schema<T> schema = getSchema(cls);
            return ProtostuffIOUtil.toByteArray(obj, schema, buffer);
        }catch (Exception e){
            throw new IllegalStateException(e.getMessage(),e);
        }finally {
            buffer.clear();
        }
    }

    /**
     * 反序列化 （字节数组 -> 对象）
     * @param data
     * @param cls
     * @param <T>
     * @return
     */
    public static <T> T deserialize(byte[] data,Class<T> cls){
        try {
            T message=(T)objenesis.newInstance(cls);
            Schema<T> schema=getSchema(cls);
            ProtostuffIOUtil.mergeFrom(data,message,schema);
            return message;
        }catch (Exception e){
            throw new IllegalStateException(e.getMessage(),e);
        }
    }



}
